1、首先创建一个子组件，返回 React.createContext(‘默认参数’)
import React from ‘react’
// 创建context
export default React.createContext(‘默认参数’)
2、在父组件引入这个子组件
import React, { useState } from ‘react’
import B from ‘./b’
import ThemeContext from ‘./c’
<ThemeContext.Provider>
</ThemeContext.Provider>
3、想要通过B组件 将父组件传值到子组件
只能用value传
const [ name ] = useState(‘小花’)
<ThemeContext.Provider value={
{name, onClick}}>
</ThemeContext.Provider>
4、子组件接受
import React, { useContext } from ‘react’
import ThemeContext from ‘./c’
export default function A() {
const { name}=useContext(ThemeContext)
return (
{name}
)
}
5、子传父用onclick
父组件用创建onclick方法
子组件解构调用